4thTimeLucky

Good point about the state recognising an illegal union in the case of incest.

But just because a relationship is legal does not mean that the state must accept its conversion into a marriage relationship.
Take for example, the love of two 15 year olds - legal, but not marriageable.'

I would contend (in devil's advocate role) that the reason that the state is allowed (if it really is) to make incest illegal is that it undermines the traditional family unit [not because of genetic problems, because the state cannot prevent adults with inheritable genetic diseases from procreating or marrying].
In the case of incest the threat to the traditional, married family unit is a direct one, so the relationship itself must be made illegal. In the case of homosexuality the threat to the traditional, married family unit comes when they request to marry. Therefore the state can intervene at that point to make gay marriage illegal.

So my questions would be:
Q1. Is the state allowed to rule activities illegal that undermine the traditional, married family unit as it understands it?
Q2. If yes, then could homosexuality not be considered a threat to the unique importance of the traditional, married family unit?
Q3. If no, then on what basis is the state allowed to rule incest illegal?


*devil's advocate*

EDIT:> Actually, I don't think much of Q2. It seems pretty obvious to me that allowing homosexuals to marry doesn't undermine the institution of marriage, in fact it may strengthen it by allowing it bind more loving couples and gain importance through prevalence. But if anyone thinks that homosexual marriage would undermine the tradional, married family unit then please feel free to join in on this one.

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